Methodology for computing
soil physical health index: Soil physical
rating score chart by Gupta and Abrol (1993)
was used for rating different soil physical
parameters. Scores for different soil
parameters were given as per the rating
chart tables for both upland crop and
lowland rice. In these tables three important
soil parameters namely soil depth, depth of
water table and land slope have not been
mentioned as in the surveyed area soils were
deep (>1 m), depth of water table was >1.5 m
and land slopes were <2 %. The parameters
considered for computing soil physical
health assessment were Bulk density ( BD in
Mg m-3), saturated hydraulic conductivity
(Sat HC in cm h-1), available water
retention capacity (AWRC in cm m-1), organic
carbon (OC in %) and non-capillary pores (NCP
in %).
The above rating chart was prepared by
analyzing the soil physical and yield data
of 30 years of research experiments reported
in All India coordinated research project on
�Improvement of soil physical conditions to
increase agricultural production of
problematic areas�. These experiments were
conducted for different cropping systems at
various locations with different soil types
and agro climatic zones. Same ranges of soil
parameters were assigned different rating
values under rice and wheat cultivations
because optimum soil physical environment
required for their growth were different.
For a given site, each of these parameters
was assigned a rating value corresponding to
its actual value by referring to rating
chart. Each of this parameter was given a
score of 1 if the parameter value lies
within the optimum range. If the value lies
below or above the critical limit, a score
less than 1 were given. Greater the
deviation of parameter value from optimum
range, lesser the score given to it. The
product of rating values of all the eight
parameters gave the physical rating index
(PI). PI was an indicator of overall soil
physical health status. For range of PI
>0.75, 0.50-0.75, 0.25-0.50 and <0.25, soil
physical health status and accordingly its
production potential could be labeled as
very good, good, medium or poor,
respectively.

R. P. Gupta and I. P. Abrol, 1993. A study
of some tillage practices for sustainable
crop production in India. Soil and Tillage
Research, 27:253-272.